ok i was just messing with my carb because i want better gas mileage. so i leaned it out and started hearing a noise like ding ding ding or maybe it was ping ping ping. well if i richened it up it would go away. should i lean it back out since my idle in park right now is like 800rpms and get higher octane gas or just leave it the way it is with 87 octane?

If you're leaning it using the idle mixture screws, that's all you're going to lean out, the engine at idle.

Making jet and rod changes and possibly the pump cam (depending on what carb you're talking about) is what you need to do if you're looking to get better mileage, and that's where you need to be vigilent. You can severely alter your performance and lean at WOT, under load is not a good thing. Read your plugs.

If your leaning it out, you might save a Few MPG , but If you go too far, your going to have other problems, Like starvation, and heating.

The Choke removal might save you a bit, If it were Mal~adjusted to begin with, But you'll regret it the first time you come out from Work / School after it's sat in a snow covered parking lot for 8 hours on a slightly weak battery....

I know of which I speak, I have one vette that has the choke plate defeated (but not removed) because of secondary lockout problems, (that I need to find time to repair) On a first start of the day, It takes minimum 30 seconds or more of constant cranking to start...

and if it has sat for a few weeks, I have to charge the battery, Or hit it with start fluid, before I even try to start it. Cuz I know it (the battery) will die before it starts, So you might want to rethink that. What little it may save you in Fuel, will be consumed on the first Tow call...Put it back and adjust./Repair it properly.

If your getting pinging, Raise The octane rating of your fuel, And Check your timing ..Look at the specs for your car , 350 should be somewhere around 12 to 18 initial, with Vacuum advance removed and plugged. Then look at your total timing, should be around 34 to 38 ... If you can't get that look at your advance weights...

Check your EGR valve for leaks and or improper operation. This can cause stumble, bad idle, poor fuel consumption, pinging. If you apply full vacuum to it it should pull the valve and the engine will die if it's working right..Spray Carb Cleaner around the base of the EGR to test for leaks, If it speeds up the gasket is leaking.

PROPERLY adjust your jets...

Carefully Turn them all the way in,
([color=red]don't crank on them or you'll ruin them by scaring the jet[/color])

Back each Jet out 3 turns, (6 half turns) Then Start the car...

SLOWLY turn the jets until you achieve The HIGHEST idle from each jet.

Then, Turning about a 16 th of a turn at a time up and down SLOWLY listen for the HIGHEST idle with no RANDOM Stumble, misses or tiny "Pop's" out the exhaust...

[ANDWAIT at least 15 seconds for the engine to stabilize BEFORE you turn the jet again..Else you'll tune right through the "Sweet Spot".

The key to this is TAKE your time, To do this for Best performance and Fuel economy on an otherwise properly Functioning Carb, requires you Slowly make adjustments and WAIT for the engine to "CLEAR " it's lungs before moving on..

If this is your first time, Plan a whole Saturday afternoon to do it If you want to get it perfect..and If you LISTEN carefully, as you make adjustments, you'll be able to hear the "Pitch " of the Carb change as you fatten or lean it...remember how it sounds and it'll help on the next carb you adjust...

Finally, when you think you have it right, Go to the back and cup your hands around the exhaust and inhale...Do you smell raw fuel? If you do.. Back to the Jets or The Carb may have another problem..Like" Hung" Secondary Needles...If the jets don't respond or have little Effect while turning them, It's probably Time for a rebuild.

800 RPM curb idle on a 350 is right about center of the spectrum The book say's 950 Curb and 650 Drive or reverse For an Automatic, and 750 and 550 -650 for a manual...If it dosn't Run on when you shut it off, leave it alone.If it does, look at the timing first for advance before backing the idle down..

i just turned the idle screws in til they wouldnt anymore i didnt tighten them or turn them in fast or hard just smoothly.
i started the car after tuning the screws 6 half turns and am now at 10 grand idle.

the numbers on block btw came back as a 305 so its a 305.

ok so i listened to the exhaust and i hear lololololololo and a little bit of in between the lololololo a gluglu or something like that. thats the cam correct? the idle doesnt move when that noise happenes.

ok took it for a drive didnt notice much just a little more power.
i tryed adjusting the screws like you said after the 6 half turns out. well i didnt notice anything until i cranked them back in about 3/4 turns each. then i would get the idle down to about 900 and any further the motor would shake like i was going by my attienna on the fender. it would stay there fine not really moving at 10grand but then around less then 900 or maybe a little less it would shake.

what should i do?
adjust the screws til just before i change the idle and leave it at those high rpms?
or adjust it til i get a steady tach needle at 800rpms?

i did notice tho i dont have that smoke coming out my crankcase anymore while its like this.

you have an idle speed screw that you need to back off. Adjust the mixture screws until you have the highest rpm, then adjust the speed screw until you have the rpm that you want. Then readjust the air again. Get a balance with these two adjustments.

The air adjusters shouldn't be over 1-3 or so turns, 10 is way to much, probably because the idle speed screw is holding the throttle plate open to far after you get the mixture screws set.

yes thats what it does it goes tralalalalalallalalalala.....no pauses.
which screw is for what? and how far do i turn them from 3 turns out? and whice way. i never did this before as you can see.

its a 600cfm edelbrock carb.

two screws in front. right now i have both set the same. 3 turns from turned in and cant go any further.
EDIT: also after i took it for a drive it idles at 900rpms now. so im guessing that is good.

well i just got back from a buddy of mineand he said he set his carb like this: car running turn screws in til it bogs then a quarter turn out. and his truck runs good. except the timing chain he changing right now

The two on the front are the air adj. The one on the drivers side sets the idle speed.

There is no set amount of turns for the air screws. Read the previous posts.

Turn each screw in until it stops gently. Then back them out a couple of turns. Start engine, then start turning it out or in which ever helps the most very slowly until the idle gets rough, then in or out until it smooths out the most, you will have to do this several times, one and then the other, until you get the highest best idle, all the time keeping the speed adj. down as far as you can without it stalling out. Both screws may not be the same amount of turns.
You can't just set them a given amount of turns, you have to tune each one separate.

ok i think it got it near set right. i just set them so that it would idle rough or w/e with the screws oved around to seperate spots the one on the drivers side is turned in more. i did notice more power since i did this. now i can just punch it from a slow roll and they spind then i shift into second and they still spin and its a 305 with a couple mods. i cant wait til i get my headers on then evevn more power. also i need to put back on the tires with good meat cause right now they are about 3/4 bald.
EDIT: im gonna go by this site here sounds good to mehttp://neptune.spacebears.com/cars/stories/carb.html

so you mean no matter what i do to those two screws on the front my gas milage will stay the same?
im starting to not like my carbed motor since everytime you start the car it uses up like 1/4 gal or w/e it is?

THOSE ARE THE IDLE MIXTURE SCREWS sorry for yelling, they will lean the idle out, or richen it up, given their positioning. all they affect is the idle.
if you want to lean it out in the cruise mode, (open throttle) you'll need to swap out the metering rods and kick down springs.

not busting your balls here, but do you have a manual that came with it? reason i ask, is there is a chart in it that will show you which way to go metering rod and spring wise..... like i said, it's on the edelbrock website too. you need a calibration kit. it has several metering rods and springs in it to let you tune it to your liking. the good news, you won't have to pull the carb to do any of this, unless you drop something into it.

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